APPARATUS AND METHODS FOR CLAMPING A MITRAL VALVE
An apparatus for repairing or replacing a mitral valve and a method of using same are disclosed. The apparatus has an atrial band securable to a ring-shaped ventricular band. The ventricular band has an anterior band and a posterior band connectable to the anterior band. The atrial and anterior bands each have a pair of apertures. Each of the apertures is positioned proximate to a respective terminal end of the bands. The apertures of the atrial and anterior bands are arranged to align with one another when their inner surfaces engage. Means are provided to secure the atrial band to the anterior band. When delivered and implanted, the apparatus is arranged to extend across the commissures of the heart, with atrial and anterior bands arranged to press against the atrial and ventricular surfaces of the mitral valve leaflets respectively.
This application claims priority from U.S. application No. 62/987,240 filed 9 Mar. 2020 and entitled APPARATUS AND METHODS FOR CLAMPING A MITRAL VALVE which is hereby incorporated herein by reference for all purposes. For purposes of the United States of America, this application claims the benefit under 35 U.S.C. §119 of U.S. application No. 62/987,240 filed 9 Mar. 2020 and entitled APPARATUS AND METHODS FOR CLAMPING A MITRAL VALVE.
TECHNICAL FIELDThe present invention relates to apparatus for use in repairing or replacing heart valves and methods of use thereof. In particular, the present invention relates to apparatus and methods for clamping a mitral valve.
BACKGROUNDThe mitral valve is the most complex of the human heart's valves and is commonly associated with disease. Conditions affecting the normal functioning of the mitral valve include, for example, mitral valve regurgitation, mitral valve prolapse, and mitral valve stenosis. Mitral valve regurgitation refers to the condition whereby the leaflets of the mitral valve fail to coapt into apposition during ventricular contraction, resulting in abnormal leaking of blood from the left ventricle into the left atrium. Mitral valve prolapse refers to the condition where the mitral leaflets bulge abnormally up into the left atrium causing irregular behaviour of the mitral valve. Mitral valve stenosis refers to the narrowing of the heart's mitral valve obstructing blood flow. A number of factors may affect the normal functioning of the mitral leaflets.
Although intermediate grades of impaired functioning of the mitral valve may not require treatment, severely impaired mitral valve function may result in symptoms (for example, breathlessness, fatigue, exercise intolerance), and may represent a threat to life expectancy. Often, invasive surgery must be performed to repair or replace an abnormal mitral valve.
Traditionally, repairing or replacing a mitral valve involves an open heart procedure. Open heart procedures present patients with morbidity and mortality risks and require a post-op period of convalescence that is typically several months in duration. Open heart surgery may pose prohibitive risks, or may otherwise not be ideal for some patients, including some elderly patients and patients with other health issues. Repairing or replacing the mitral valve without invasive open heart procedures may be attractive therapy for such patients.
The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.
SUMMARYThe following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.
One aspect of the invention provides an apparatus for repairing or replacing a mitral valve, in particular for clamping a mitral valve of a heart. The apparatus comprises an atrial band securable to a ring-shaped ventricular band. The ventricular band comprises an anterior band and a posterior band connectable to the anterior band. The atrial and anterior bands each have a pair of apertures. Each of the apertures is positioned proximate to a respective terminal end of the bands. The apertures of the atrial and anterior bands are arranged to align with one another when the inner surface of the atrial band engage with the inner surface of the anterior band. Means are provided to secure the atrial band to the anterior band when their inner surfaces engage.
One aspect of the invention provides a method for repairing or replacing a mitral valve. The method comprises the steps of advancing a first guide wire intravascularly through towards a ventricular surface of a mitral valve leaflet in the ventricular space, advancing a ventricular band along the first guide wire, encircling the ventricular band around the mitral valve leaflet, extending a second and third guide wire from a pair of apertures defined by an anterior band of the ventricular band, advancing the second and third guide wires through the mitral valve leaflet sequentially, advancing an atrial band along the second and third guide wires, and securing the atrial band to the anterior band.
In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions.
Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.
Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
Unless context dictates otherwise, the term “anterior” (as used herein in relation to a patient’s body and parts thereof) refers to a position that is more near the front surface of the patient's body or part thereof than the rear surface of the patient's body or part thereof.
Unless context dictates otherwise, the term “posterior” (as used herein in elation to a patient’s body and parts thereof) refers to a position that is more near the rear surface of the patient’s body or part thereof than the front surface of the patient’s body or part thereof.
Unless context dictates otherwise, the terms “percutaneous”, “percutaneously”, and the like (as used herein) refer to a method of accessing a patient’s circulatory system and/or heart through the skin, such as by needle access.
Unless context dictates otherwise, the term “antegrade” (as used herein) refers to a percutaneous approach to a mitral valve via the femoral vein, right atrium, atrial septal puncture, and left atrium (i.e. in the normal direction of blood flow through a patient’s circulatory system).
Unless context dictates otherwise, the term “retrograde” (as used herein) refers to a percutaneous approach to the mitral valve via the femoral artery, wherein the left ventricle is accessed via the aortic valve (i.e. in reverse of the normal direction of blood flow through a patient’s circulatory system).
Unless context dictates otherwise, the term “intravascular” (as used herein) means situated or occurring with a blood vessel or circulatory system.
Unless context dictates otherwise, the term “external” (as used herein in relation to a patient’s body and parts thereof) means situated outside of a patient’s circulatory system or body.
Unless context dictates otherwise, the term “transcatheter” (as used herein) refers to a method performed through the lumen of a catheter.
Unless context dictates otherwise, the term “circulatory system” (as used herein) refers to a system that circulates blood and/or lymph through a patient's body, consisting of one or more of the heart, blood vessels, blood, lymph, and the lymphatic vessels and glands.
Unless context dictates otherwise, the term “afferent” means towards the operator and away from the patient’s circulatory system or body.
Unless context dictates otherwise, the term “efferent” means away from the operator and towards the patient’s circulatory system or body.
Although the methods and apparatus of the present invention may be used for the percutaneous repair of any of the cardiac valves, the following description will focus on the repair of mitral valves. Further, while the methods and apparatus of the present invention will preferably be percutaneous and intravascular, such methods and apparatus may be used for performing open heart surgery where the heart is accessed through the myocardial tissue and/or in minimally invasive procedures where access to the heart is achieved thorascopically. Further still, while the methods and apparatus of the present invention may be used with conventional transcatheter valve prostheses, such methods and apparatus may be used with prostheses implanted through the myocardial tissue of the heart and/or prostheses implanted using minimally invasive procedures where access to the heart is achieved thorascopically.
The human heart 10, shown in
Mitral valve 30 separates left atrium 20 from left ventricle 40, and is comprised of a mitral annulus 32, leaflets (anterior 34 and posterior 36), chordae tendinae 38, and papillary muscles 39. During ventricular contraction (systole), the ventricular pressure rises, which forces displacement of mitral leaflets 34, 36 towards atrium 20 (i.e. commonly known as atrial or leaflet displacement). The length and integrity of chordae tendinae 38 determines the degree of leaflet displacement. In normal physiology, equal displacement of anterior mitral leaflet 34 and posterior mitral leaflet 36 results in contact (coaptation) between the leaflets, and consequent competence of mitral valve 30.
In circumstances where mitral leaflet 34 and/or 36 is supported by chordae tendinae 38 which are elongated or ruptured, ventricular contraction may result in excessive atrial displacement of the leaflet(s), and this may prevent coaptation between the leaflets (
The methods and apparatus of example embodiments of the present invention use existing transcatheter heart valve prostheses to percutaneously replace a mitral valve. The methods and apparatus of example embodiments of the present invention may be used to precisely secure the mitral valve leaflet (e.g., anterior mitral valve leaflet) in position during transcatheter mitral valve replacement (TMVR) procedures. This may facilitate precise percutaneous incision of the anterior mitral valve leaflet, prevents the anterior mitral valve leaflet from tearing, and avoids separation between the valve leaflet and the implanted TMVR prosthesis.
Referring to
In the natural states, atrial band 120 and/or anterior band 132 of ventricular band 122 may assume an annular curvature along its length, such that bands 120, 132 may be hyperbolic-shaped. When apparatus 100 is delivered into the heart, the annular curvatures of the bands 120, 132 are in the plane of the mitral annulus, arranged to correspond with the annular circumference of the anterior mitral annulus.
In the natural states, the inner surfaces 144, 146 of one or both of atrial band 120 and anterior band 132 of ventricular band 122 may assume a curvature with respect to the axial plane of apparatus 100. The axial plane is defined by an imaginary plane that divides apparatus 100 into atrial band 120 and ventricular band 122. In some embodiments, the degrees of curvature of one or both of inner surfaces 144, 146 of the respective atrial band 120 and anterior band 132 are about 0°, i.e., one or both of inner surface(s) 144, 146 are substantially planar, parallel to the axial plane of apparatus 100. In some embodiments, the degrees of curvatures of inner surfaces 144, 146 of the respective one or both of atrial band 120 and anterior band 132 are greater than 0° with the vertex of the curvature being at a midpoint along the length of atrial band 120 and/or anterior band 132. In such embodiments, one or both of inner surface(s) 144, 146 of atrial 120 and anterior 132 bands are convex-shaped, i.e., the pair of opposing edges extending along the length of one or both of inner surface(s) 144, 146 of atrial 120 and anterior 132 bands are curved outwardly from an imaginary line that is parallel to the axial plane of the apparatus such that one or both inner surface(s) 144, 146 may define a U-shape configuration and/or an inverted U-shape configuration. In some embodiments, inner surface 144 of atrial 120 has a U-shape configuration and inner surface 146 of anterior band 132 has an inverted U-shape configuration.
Atrial 120 and anterior 132 bands may be made of the same or different materials, including for example silicone, medical grade plastic, thermal plastic, stainless steel, metal, a metal alloy (e.g., nitinol or another nickel or titanium alloy), and titanium. Atrial 120 and anterior 132 bands may be made of materials with equal stiffness, i.e., stiffness being the extent to which the bands resist deformation in response to an applied force, typically measured in Young's modulus (E); the stiffer the material, the more resistant it is to deformation, the greater the Young's modulus. Atrial 120 and anterior 132 bands may alternatively be made of materials with different stiffnesses.
In one embodiment, inner surfaces 144, 146 of atrial 120 and anterior 132 bands are deformed to assume a curvature with respect to the axial plane of apparatus 100 when apparatus 100 is in the implanted configuration (as best seen in
In some embodiments, the relatively more flexible band (e.g., the band having a material with a lower Young's modulus) deforms to conform to the shape of the stiffer band (e.g., the band having a material with the higher Young's modulus) when the bands are secured. In one embodiment, a generally planar inner surface 144 of atrial band 120 (see
Both inner surfaces 144, 146 of bands 120, 132 may be curved. The two curved bands of different stiffness may deform into a generally planar or a curved resultant shape, with a desired curvature, in the implanted configuration.
Atrial band 120 is defined by a pair of apertures 152, 154 each one positioned proximate to one of the terminal ends 160, 162. Anterior band 132 is defined by a pair of apertures 156, 158 each one positioned proximate to one of the terminal ends 136, 138, apertures 156, 158 correspond in position with the respective apertures 152, 154 defined by atrial band 120 (i.e., in the implanted configuration, aperture 152 of atrial band aligns with aperture 156 of anterior band and aperture 154 of atrial band aligns with aperture 158 of anterior band). Apertures 152 and 156, and apertures 154 and 158 defined by the corresponding atrial band 120 and anterior band 132 provide a site of origin for guide wires 194, 196 respectively (best seen in
Referring to
In some embodiments, an attachment member 206 is provided to facilitate the connection between atrial band 120 and anterior band 132. Referring to
As best seen in
Means are provided for securing anterior band 132 to posterior band 134 of ventricular band 122 to form a closed ring.
In the
In the
In some embodiments, the average width of anterior band 132 is greater than the average width of posterior band 134 (i.e., the cross-sectional area of anterior band 132 is greater than the cross-sectional area of posterior band 134). The average width of anterior band 132 may be about two to three times greater than the average width of posterior band 134.
In some embodiments, the cross-sectional shape of posterior band 134 is a quadrilateral with four right angles (i.e., the angle bounded by each of the two sides is 90°). The right angled quadrilateral cross-sectional shape facilitates flexing of posterior band 134 in the radial direction of the apparatus 100 while restricting flexing in the axial direction. Movement in the radial plane is desirable to ensure a snug fit between the transcatheter heart valve (THV) and the posterior band 134 when the THV is implanted. Lack of movement in the axial direction is desirable to ensure that the posterior band remains in the posterior submitral space as close to the mitral annulus as possible, minimizing any downward or apical movement toward the ventricular apex or away from the annulus, to ensure that the posterior band is covered with the posterior mitral valve leaflet. This creates a seal between the THV and the apparatus with the mitral valve leaflet.
Posterior band 134 may be made of any suitable biocompatible material, such as silicone, medical grade plastic, thermal plastic, stainless steel, metal, a metal alloy (e.g., nitinol or another nickel or titanium alloy), and titanium.
Anterior 132 and posterior 134 bands may be constructed from a single continuous band. Anterior 132 and posterior 134 bands may alternatively be constructed from a plurality of modular units 192 which are arranged contiguously to create the closed ring shape (as best shown in
Tether (i.e., cuttable) guide wires are used to position apparatus 100 at the desired implantation site. Referring to
Aspects of the invention relate to methods for replacing or repairing a mitral valve of a heart.
To implant apparatus 100, a guide wire 198 is inserted into a first access site of a subject and advanced using a transcatheter approach conventionally known. Referring to
Ventricular band 122 may be advanced along guide wire 198 in a linear configuration. Referring to
Ventricular band 122 may alternatively be advanced along guide wire 198 in a bent configuration. Referring to
Distal end 220 of guide wire 198 extends through channel 123 of ventricular band 122, entering into channel 126 of anterior band 132 and exiting from channel 222 of posterior band 134. In some embodiments, distal end 220 of guide wire 198 exits the subject's circulatory system without first connecting to anterior band 132 (
Guide wires 194, 196, extending from the respective apertures 156, 158 of anterior band 132, pass through the anterior mitral valve leaflet, into the left atrium and are exteriorized therefrom through a catheter 226 (e.g., a transseptal catheter) across the atrial septum that originates at the femoral vein.
Catheter 226 is arranged to advance over each of guide wires 194, 196 sequentially for advancing guide wires 194, 196 through the anterior mitral valve leaflet 34. Referring to
In some embodiments, terminal end 227 is at the distal end 234 of catheter 226 (as best seen in
Catheter 226 is then advanced over guide wire 194 to deliver guide wire 194 to the atrium through the mitral valve leaflet as was done with guide wire 196 (
Central guide wire 204, extending from central aperture 200 or 202 of anterior band 132, passes through the left ventricle 40, aortic valve 50 and the aorta 60 and is exteriorized at the femoral artery (the first access site). Central guide wire 204 is later used to guide the incision of the mitral valve leaflet 34 from the left ventricle 40, after the attachment of atrial band 120 onto the anterior mitral valve leaflet 34 (as explained in the following paragraph). The proximal ends of guide wires 194, 196, 204 are all exteriorized at the femoral artery access site, remaining outside of the patient, while the opposing distal ends being attached to anterior band 132 during the initial delivery of atrial band 132 (
Snared guide wires 194, 196 pass through the left atrium 20 of the heart, cross the atrial septum, and are exteriorized on the venous side through the femoral vein. Snared guide wires 194, 196 are delivered to the atrial side to be used for delivery of atrial band 120 (
As illustrated in
Unless the context clearly requires otherwise, throughout the description and the claims:
- “comprise”, “comprising”, and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”;
- “connected”, “coupled”, or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof; elements which are integrally formed may be considered to be connected or coupled;
- “herein”, “above”, “below”, and words of similar import, when used to describe this specification, shall refer to this specification as a whole, and not to any particular portions of this specification;
- “or”, in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list;
- the singular forms “a”, “an”, and “the” also include the meaning of any appropriate plural forms.
Words that indicate directions such as “vertical”, “transverse”, “horizontal”, “upward”, “downward”, “forward”, “backward”, “inward”, “outward”, “vertical”, “transverse”, “left”, “right”, “front”, “back”, “top”, “bottom”, “below”, “above”, “under”, and the like, used in this description and any accompanying claims (where present), depend on the specific orientation of the apparatus described and illustrated. The subject matter described herein may assume various alternative orientations. Accordingly, these directional terms are not strictly defined and should not be interpreted narrowly.
Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions, and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be apparent to the skilled addressee, including variations obtained by: replacing features, elements and/or acts with equivalent features, elements and/or acts; mixing and matching of features, elements and/or acts from different embodiments; combining features, elements and/or acts from embodiments as described herein with features, elements and/or acts of other technology; and/or omitting combining features, elements and/or acts from described embodiments.
It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions, omissions, and sub-combinations as may reasonably be inferred. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.
While a number of exemplary aspects and embodiments are discussed herein, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof.
While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope.
Claims
1. An apparatus for clamping a mitral valve, the apparatus comprising:
- a ventricular band having an anterior band with a first terminal end and a second terminal end, the first and second terminal ends securable to the respective first and second terminal ends of a posterior band to form a closed ring;
- a pair of spaced-apart apertures defined by the anterior band positioned proximate to a respective first and second terminal ends thereof;
- an atrial band having an inner surface engageable with an inner surface of the anterior band, the atrial band defining a pair of spaced-apart apertures positioned proximate to a respective first and second terminal ends thereof for alignment with the pair of apertures defined by the anterior band;
- means for securing the atrial band to the anterior band; and
- means for securing the anterior band to the posterior band.
2. The apparatus according to claim 1 wherein the ventricular band and the atrial band are made of a flexibly deformable material, the ventricular and atrial bands are deformable between a natural state when the apparatus is in an unsecured configuration and a deformed state when the apparatus is in an implanted configuration.
3. The apparatus according to claim 2 wherein when the anterior and atrial bands are in the natural states, one or both of the inner surfaces of the anterior and atrial bands have a curvature with respect to the axial plane of the apparatus.
4. (canceled)
5. The apparatus according to claim 3, wherein when the anterior and atrial bands are in the natural states, one or both of the inner surfaces of the anterior and atrial bands have a U-shape configuration or an inverted U-shape configuration in the axial plane of the apparatus.
6. (canceled)
7. The apparatus according to claim 2 wherein when the anterior and atrial bands are in the natural states, one or both of the inner surfaces of the anterior and atrial bands are substantially planar in the axial plane of the apparatus.
8. The apparatus according to claim 2 wherein the inner surfaces of the anterior and atrial bands have the same shape or different shapes when the bands are in the natural states.
9. (canceled)
10. The apparatus according to claim 2 wherein when the anterior and atrial bands are in the deformed states, the inner surfaces of the anterior and atrial bands are deformed to assume a curvature or a substantially planar shape with respect to the axial plane of the apparatus.
11. (canceled)
12. The apparatus according to claim 1 wherein the atrial band and the anterior band are constructed from a material with equal stiffness or different stiffness.
13-14. (canceled)
15. The apparatus according to claim 1 wherein the atrial and anterior bands have an annular curvature in the natural and deformed states.
16. The apparatus according to claim 1 further comprises an attachment member extending from the atrial band at a portion proximate to the second terminal end thereof, the attachment member comprises a curve section extending from the portion to a straight section.
17. The apparatus according to claim 16 wherein the attachment member defines a channel extending through the straight and curved sections.
18. The apparatus according to claim 16 wherein the anterior band defines a channel extending from an opening defined by an upper surface of the anterior band proximate to the second terminal end of the anterior end to a closed end proximate to the first terminal end of the anterior band, the channel dimensioned to receive the straight section of the attachment member.
19. The apparatus according to claim 18 further comprising a guide wire extendable through the channel of the anterior band and the attachment member.
20. The apparatus according to claim 1 wherein the means for securing the atrial band to the anterior band comprises a pair of locking members each insertable into one of the apertures defined by the atrial and anterior bands.
21. The apparatus according to claim 1 wherein the means for securing the anterior band to the posterior band comprises a hook extending from the first terminal end of the posterior band, the hook connectable with a closed loop extending from the first terminal end of the anterior band.
22. The apparatus according to claim 1 wherein the means for securing the anterior band to the posterior band comprises a slot defined by the first terminal end of the anterior band, the slot dimensioned to snugly receive the first terminal end of the posterior band.
23. (canceled)
24. The apparatus according to claim 1 wherein the means for securing the anterior band to the posterior band comprises a connector having a pair of connecting members respectively insertable into a hole defined by each of the first terminal ends of the anterior and posterior bands.
25-26. (canceled)
27. The apparatus according to claim 1, wherein the posterior and anterior bands are constructed from a single continuous band, or from a plurality of modular units.
28. (canceled)
29. The apparatus according to claim 1, further comprising a central aperture defined by one or both of the atrial and anterior bands, wherein the central aperture is positioned midway between the pair of spaced-apart apertures defined by the atrial and anterior bands, and wherein the apparatus further comprises a guide wire extending from the central aperture.
30-35. (canceled)
36. The apparatus according to claim 1 further comprising a channel extending through a length of the posterior band, and a guidewire extending through the channel of the posterior band.
37-60. (canceled)
Type: Application
Filed: Mar 5, 2021
Publication Date: Feb 2, 2023
Inventor: Peter Lloyd SKARSGARD (Vancouver, CA)
Application Number: 17/789,601